// Licensed to Apache Software Foundation(ASF) under one or more contributor
// license agreements. See the NOTICE file distributed with
// this work for additional information regarding copyright
// ownership. Apache Software Foundation(ASF) licenses this file to you under
// the Apache License, Version 2.0 (the "License"); you may
// not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

package util

func Paginate(data []interface{}, page, size int) []interface{} {
	if data == nil || len(data) == 0 {
		return data
	}

	count := len(data)
	var pageCount int
	if count%size == 0 {
		pageCount = count / size
	} else {
		pageCount = count/size + 1
	}

	var fromIndex, toIndex int
	if page > pageCount {
		page = pageCount
	}
	if page != pageCount {
		fromIndex = (page - 1) * size
		toIndex = fromIndex + size
	} else {
		fromIndex = (page - 1) * size
		toIndex = count
	}

	return data[fromIndex:toIndex]
}
